/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.feilong.lib.net.io;

import java.io.IOException;

/**
 * The CopyStreamException class is thrown by the org.apache.commons.io.Util
 * copyStream() methods. It stores the number of bytes confirmed to
 * have been transferred before an I/O error as well as the IOException
 * responsible for the failure of a copy operation.
 * 
 * @see Util
 * @version $Id$
 */
public class CopyStreamException extends IOException{

    private static final long serialVersionUID = -2602899129433221532L;

    private final long        totalBytesTransferred;

    /**
     * Creates a new CopyStreamException instance.
     * 
     * @param message
     *            A message describing the error.
     * @param bytesTransferred
     *            The total number of bytes transferred before
     *            an exception was thrown in a copy operation.
     * @param exception
     *            The IOException thrown during a copy operation.
     */
    public CopyStreamException(String message, long bytesTransferred, IOException exception){
        super(message);
        initCause(exception); // merge this into super() call once we need 1.6+
        totalBytesTransferred = bytesTransferred;
    }

    /**
     * Returns the total number of bytes confirmed to have
     * been transferred by a failed copy operation.
     * 
     * @return The total number of bytes confirmed to have
     *         been transferred by a failed copy operation.
     */
    public long getTotalBytesTransferred(){
        return totalBytesTransferred;
    }

    /**
     * Returns the IOException responsible for the failure of a copy operation.
     * 
     * @return The IOException responsible for the failure of a copy operation.
     */
    public IOException getIOException(){
        return (IOException) getCause(); // cast is OK because it was initialised with an IOException
    }
}
